Structural optical and magnetic properties of nanostructured ceria based dilute magnetic semiconductors

Abstract

The diluted Magnetic semiconductor (DMS) is referred to as a semiconductor in which a prescribed fraction of host cations is replaced by transition metal ions or rare earth elements ions as magnetic elements. In the recent years, large efforts have been devoted to the investigation of DMS materials due to their potential application in spintronic devices. The operation of spintronic devices depends on charge and spin of electrons. Practical applications of DMS materials require both Curie temperature at/above room temperature and the ferromagnetic properties, which should be intrinsic and not due to the presence of magnetic clusters of dopants. Based on the above perspectives, the present thesis focuses on synthesis and characterization such as structural, optical and magnetic behaviors of some rare earth elements and transition metal ions doped and codoped CeO2 based materials. Chapter 1 presents the significances of nanostructured materials and their unique properties. A brief description of properties of semiconducting oxides and dilute magnetic semiconductors are discussed below. This chapter also describes the structure, defects and applications of cerium oxide nanoparticles and literature review on the relevant work is included. Chapter 2 summarizes numerous synthesis and characterization techniques adopted for nanocrystalline materials and their fundamental principles and operational aspects have also been presented. Chapter 3 discusses the preparation and characterization of pure and Pr doped CeO2 nanoparticles synthesized by using citrate-nitrate auto combustion technique. newline